1. Field of the Invention
The present invention relates to a drive apparatus for driving a moving element to move the same in a predetermined direction using elliptical vibration of a transducer and to an image pickup apparatus such as a digital camera which performs shake compensation by the drive apparatus.
2. Description of the Related Art
A camera is a conventional example of an image pickup apparatus having shake compensation function. As shake compensation function which the camera has, there is known shake compensation function wherein: shaking in a pitch direction of the camera and shaking in a yaw direction of the camera are detected using shake detecting means such as an angular velocity sensor; and a portion of an image pickup optical system or an image pickup device is shifted respectively independently in a horizontal direction and a vertical direction in a plane perpendicular to a photographic optical axis in such directions as to compensate for shaking based on detected shake signals, thereby compensating for shakes of images on an image pickup surface of the image pickup device.
In a shake compensation mechanism achieving such shake compensation function, drive means is used which moves some of photographic lenses or the image pickup device itself in the horizontal direction and the vertical direction in a plane perpendicular to the photographic optical axis in order to compensate for shaking. The drive means is required to have high responsiveness in order to operate following shaking, precise drive (minute drive) and self-holding property to hold a position of a moving element when power is off.
For such requirements, a drive apparatus is conceivable as a shake compensation mechanism to which a transducer is applied, in which two transducers generating elliptical vibration in their surfaces and two moving elements pressed by the transducers are combined.